Highly efficient luminaire having optical transformer providing precalculated angular intensity distribution and method therefore

ABSTRACT

A highly efficient luminaire. The luminaire includes a light source that emits light. The emitted light is redirected by a light transformer having a curved circular reflective interior surface, the reflective interior surface reflecting the light in a predetermined pattern. A substantial amount of light being may be reflected close to an axis coincident with a radial line defining a radius of the circular reflective interior surface. Additionally, a substantial amount of light may be reflected in a pattern with low divergency or parallel with an axis of the light transformer. The light is transmitted to the exterior of the luminaire by an optical window.

This application is a continuation application based on U.S. Ser. No.09/566,521 filed on May 8, 2000, now U.S. Pat. No. 6,543,911 issued Apr.8, 2003.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention is directed generally to lighting systems. Moreparticularly, the present invention is directed to light transformingdevices that provide a precisely determined light distribution pattern,such as those used for navigation, obstructions and other signal lights.

2. Description of Related Art

Presently, lighting systems are used to mark obstructions and curves onroadways and paths on airport taxiways and runways. For example,airports incorporate a system of lighting to provide guidance toapproaching and taxiing aircraft. Thousands of halogen lamps can be usedin airports. Unfortunately, these lamps require excessive amounts ofpower.

In roadway lighting systems, lamps are placed around the obstructionsand along roadway curves to signal the presence of the obstructions andcurves to drivers. These lighting systems do not sufficiently redirectlight in an optimal pattern for drivers. For example, the lamps do notprovide adequate light to drivers located far away from the lamps.Accordingly, the lamps also do not compensate for an inverse squarerelationship of illuminance to distance as a driver approaches the lamp.In particular, the lamps do not adjust for the fact that a driver cansee the lamp better when the driver is closer to the lamp. Additionally,most of such signal devices direct only a portion of light emitted by alight source in a useful pattern. Accordingly, they have low efficiency.

SUMMARY OF THE INVENTION

The present invention provides a method and apparatus for a highefficiency redirected light emitted by a light source in a predeterminedpattern by using an optical transformer with a precisely calculatedreflective surface. In one embodiment, the present invention providesemitted light redirected by a light transformer having a curved circularreflective interior surface, the reflective interior surface reflectingthe light in a predetermined pattern. For example, the reflectiveinterior surface reflects the light with a substantial amount of lightbeing reflected close to an axis coincident with a radial line defininga radius of the circular reflective interior surface. The light istransmitted to the exterior of the light transformer by an opticalwindow.

In another embodiment, the present invention provides a lightredirecting device for transmitting light with low divergence orsubstantially parallel with an axis of light direction. The device caninclude a first total internal reflection surface, a first memberincluding a portion of the first total internal reflection surface, afirst planar optical window located at an end of the first member, thefirst planar optical window being substantially perpendicular to theaxis of light direction, and an aspheric lens adjacent to the firstmember. The device can further include a second total internalreflection surface symmetrical across the axis of light direction withthe first total internal reflection surface, and a second memberincluding a portion of the second total internal reflection surface, thesecond member symmetrical across the axis of light direction with thefirst member. The device can additionally include a second planaroptical window located at an end of the second member, the second planaroptical window being substantially perpendicular to the axis of lightdirection, the second planar optical window further being symmetricalacross the axis of light direction with the first planar optical window.

In another embodiment, the present invention provides a lightredirecting device that can include a first end that receives light froma light source, a second end that outputs the received light, the secondend located on an opposite end of the device from the first end, a firstmember located on a third end of the light redirecting device the firstmember having an outer wall comprising a total internal reflectionsurface, a second member located on a fourth end of the lightredirecting device, the fourth end located on an opposite end of theredirecting device from the third end, the second member having an outerwall comprising a total internal reflection surface, and an axis locatedbetween the third end and the fourth end, the axis being perpendicularto the first end. The first face and the second face can redirect thereceived light in a direction of the second end.

In another embodiment, the present invention provides a method fordesigning a reflective surface for a light transformer that can includethe steps of receiving maximum and minimum output angles, receiving alocation of a portion of the light transformer with respect to a lightsource that provides light, and iteratively, point-by-point, calculatingan optical transformer reflective surface by providing for eachincrement of an input angle, an associated increment of the output anglewhich is consistent with predetermined output intensity distribution toreflect light provided by the light source according to the receivedmaximum and minimum output angles based on the received location of aportion of the light transformer.

In another embodiment, the present invention provides an apparatus fortransforming and emitting light that can include a light source thatemits light, a light transformer having a curved circular reflectiveinterior surface, the reflective interior surface reflecting the lightemitted by the light source in a predetermined pattern with asubstantial amount of light being reflected close to an axis coincidentwith a radial line defining a radius of the circular reflective interiorsurface and an optical window the transmits the light to the exterior ofthe light transformer. The reflective interior surface can reflect thelight at an angle α to achieve an intensity proportional to 1/(tan² α).The reflective interior surface can further reflects light rays of thelight at different angles to compensate for an inverse proportionalrelationship between perceived intensity and distance from a lightsource.

BRIEF DESCRIPTION OF THE DRAWINGS

The preferred embodiments of the present invention will be describedwith reference to the following figures, wherein like numerals designatelike elements, and wherein:

FIG. 1 is an exemplary perspective view of a light transformer accordingto one embodiment;

FIG. 2 is another exemplary perspective view of a light transformeraccording to one embodiment;

FIG. 3 is a cross-sectional diagram of a semi-flush omnidirectionalluminaire according to another embodiment;

FIG. 4 is an exemplary perspective view of a light transformer accordingto another embodiment;

FIG. 5 is an exemplary top view of a lighting system for a lighttransformer according to another embodiment;

FIG. 6 is a cross-sectional diagram of a light transformer according toanother embodiment;

FIG. 7 is another cross-sectional diagram of a light transformeraccording to another embodiment;

FIG. 8 is an exemplary block diagram of a light transformer designsystem;

FIG. 9 is an exemplary block diagram of a light transformer designmodule;

FIG. 10 is an exemplary illustration of an omnidirectional lighttransformer system;

FIGS. 11(a)-11(c) are exemplary illustrations of inverse square lawcompensation using source luminous intensity;

FIG. 12 is an exemplary illustration of how a reflective surface isdesigned;

FIG. 13 is an illustration of an exemplary flowchart for the design of alight transformer;

FIGS. 14(a)-14(c) are exemplary illustrations of a system that providesan omnidirectional light pattern in a horizontal plane with precisionpredetermined luminous intensity distribution in a vertical plane;

FIGS. 15(a) and 15(b) are exemplary illustrations of a resultingenvelope and a overlapping intensity distribution pattern of a lightingsystem;

FIG. 16 is an exemplary illustration of a vertical cross section of atoroidal precision optical transformer; and

FIG. 17 is an exemplary illustration of an optical transformer for anelevated omnidirectional light transformer.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 is an exemplary perspective view of an integrated omnidirectionallight transformer 100 according to one embodiment. The integrated lighttransformer 100 can include an optical window 110 and a support 120. Theoptical window 110 may comprise an omnidirectional window or it maycomprise any other means for transmitting light, such as lenses,diffusers or open areas. In operation, when it is desirable todistribute light out of the light transformer 100 in a 360 degreepattern, the light transformer 100 can be circular as illustrated. Othershapes and various masks can be used to effectuate different lightdistribution patterns. For example, part of the optical window 110 maybe masked in order to distribute light out of only a portion of thelight transformer 100.

FIG. 2 is another exemplary perspective view of the light transformer100 according to one embodiment. FIG. 2 illustrates that the lighttransformer 100 can further include an arbitrary aspherical reflectivesurface 130. The reflective surface 130 may be a curved conicalreflective interior surface. In operation, light can be projected fromthe bottom of the light transformer onto the reflective surface 130. Thereflective surface 130 can then reflect the light through the opticalwindow 110 out of the light transformer 100.

FIG. 3 is a cross-sectional diagram of a semi-flush omnidirectionalluminaire semi-flush omnidirectional luminaire 300 according to anotherembodiment. The semi-flush omnidirectional luminaire 300 can include alight transformer 100, a light source 310, a shell 320, a connector 330,a printed circuit board (PCB) 340 and light rays 350-352. The semi-flushomnidirectional luminaire 300 can also include a gasket plate 360, a rib370, a seal 380 and a bond 390. The light source 310 may be a lightemitting diode or any other device that emits light. The connector 330may provide an electrical connection to outside circuitry that providespower and control for the semi-flush omnidirectional luminaire 300. ThePCB 340 can provide electrical connection for the light source 310, theconnector 330 and useful circuitry for operating the semi-flushomnidirectional luminaire 300. The PCB 340 can also provide controlcircuitry and a power source so that the semi-flush omnidirectionalluminaire 300 can operate autonomously from outside circuitry and power.

In operation, the light source 310 emits light rays 350-352 towards thereflective surface 130. The light rays 350-352 are reflected inaccordance with the curvature of the reflective surface 130. A ray witha minimal angle with respect to the vertical axis is reflected in adirection of the maximum elevation (ray 352), and a ray with a maximumangle is reflected in a direction of minimum elevation (ray 350).Therefore, the waist of the outgoing beam will be formed in order tominimize the vertical size of the transmissive wall. Preferably, ahigher percentage of the light rays 350-352 are reflected along the pathof ray 350.

For example, 70% of the light emitted from the light source 310 can bereflected substantially along the path of light ray 350, 10%substantially along the path of light ray 352 and the remaining 20%substantially between paths 350 and 352. Therefore, the luminaire 300will have a luminous intensity higher at lower angles, and about alllight emitted by the light source will be directed in a predeterminedpattern. In particular, the luminaire 300 can redirect the light so thatilluminance at a long range distance (i.e. at the lower observationangles) will be equal to illuminance at a short range distance (i.e. atthe higher observation angles). Therefore, as a driver in a carapproaches the luminaire 300, the driver can perceive light of equalintensity at long distances and at short distances from the luminaire300.

FIG. 4 is an exemplary perspective view of a luminaire 500 according toanother embodiment. The luminaire 500 can include a light transformer600 and a lighting system 800 comprising multiple light sources 700. Inoperation, the light transformer 600 can be placed over the lightingsystem 800 to receive and distribute light from the light sources 700.

FIG. 5 is an exemplary top view of a lighting system 800 for a lighttransformer according to another embodiment. The lighting system caninclude light sources 700. The light sources 700 can be LEDs or anyother device useful for emitting light. The light sources 700 maysurround the lighting system 800 or the light sources may partiallysurround the lighting system 800 to only emit light out of part of thelighting system 800.

FIG. 6 is an exemplary cross-sectional diagram of a light transformer600 according to another embodiment. The light transformer 600 mayinclude a window such as a window 610, an aspherical lens 620, totalinternal reflection surfaces (TIR) 630 and 635 and clear windows oroptical windows 640 and 645. The TIR surfaces 630 and 635 may be curvedcircular reflective interior surfaces or arbitrary aspherical reflectivesurfaces.

FIG. 7 is another exemplary cross-sectional diagram of a lighttransformer according to another embodiment. FIG. 7 illustrates a lightsource 700 distributing light rays 710-750 to a portion of the lighttransformer 600. The light source may be a LED or any other deviceuseful for emitting light. In operation, the light source 700 radiateslight rays 710-750 towards the light transformer 600. The light rays710-750 enter the light transformer 600 at the window 610. Asillustrated, light ray 730 propagates straight from the light sourcealong an axis coincident with a radial line defining a radius of thecircular reflective interior surface. Those light rays 720, 730 and 740which travel directly to the surface 620 are refracted in a directionwith low divergence or substantially parallel to light ray 730. Thoselight rays 750 and 760 which travel to surfaces 630 and 635 arereflected through clear windows 640 and 645 in a direction with lowdivergence or substantially parallel to light ray 730.

FIG. 8 is an exemplary block diagram of a light transformer designsystem 900. The light transformer design system 900 can include a designprocessing unit 910, an input device 920, an output device 930 and adatabase 940. The design processing unit 910 may be a processor, apersonal computer, a mainframe computer, a palm computer or any otherdevice useful for processing data. The input device 920 may be akeyboard, a voice recognition system, a modem, a scanner or any otherdevice useful for inputting data. The output device 930 may be a videomonitor, a printer, a modem or any other device useful for outputtingdata. The output device 930 may also be a machining system formanufacturing a light transformer. The database 940 may be located inmemory on the design processing unit 910, on a compact disk, on a floppydisk, on a hard drive or on any other device useful for storing data.

In operation, the input device 920 is used to input data to the designprocessing unit 910. The data may be input by a user of the system 900.The design processing unit 910 can process the data and store the dataon the database 940. The design processing unit 910 can also retrievedata from the database 940 for processing. The design processing unit910 can further send data to the output device 930. The output device930 may print out or display the data to a user. The output device 930may additionally machine a light transformer based on the data.

FIG. 9 is an exemplary block diagram of a light transformer designmodule 1000. The light transformer design module 1000 may include acontroller 1050, a memory 1040, an input/output (I/O) interface 1010, adatabase interface 1020 and a bus 1030. The controller 1050 controls theoperation of the light transformer design system 900 and communicateswith the input device 920 and the output device 930 through the networkinterface 1010 and the database 940 via the database interface 1020. Inoperation, when a designer uses input device 920, for example, thedesign processing unit 910 may be accessed and the communication signalsmay be routed by the controller 1050 to the design processing unit 910.

In an exemplary embodiment, the controller 1050 operates in accordancewith the invention by receiving maximum and minimum output angles andreceiving a location of a portion of the light transformer with respectto a light source. The controller 1050 can iteratively calculate pointson the light transformer to reflect light provided by the light sourceaccording to the received maximum and minimum output angles based on thereceived location of a portion of the light transformer.

The design module 1000 can be used to create an arbitrary asphericalreflective surface, for example, reflective surfaces 130, 630 or 635that will provide equal omnidirectional patterns in a horizontal spacewith precisely predetermined luminous intensity distribution in thevertical plane utilizing a single light source or multiple light sourceswith given photometric characteristics.

FIG. 10 is an exemplary illustration of an omnidirectional lighttransformer system 1100. The omnidirectional light transformer system1100 can include an omnidirectional light transformer 1110 such as thelight transformer 100 that has an omnidirectional window 1120 and anaspherical reflective surface 1130. The omnidirectional lighttransformer system 1100 can also include a light source 1140 such as anLED.

The aspherical reflective surface 1130 can be designed so that all lightrays emitted from the light source 1140 are reflected through theomnidirectional window 1120 at an angular domain between α′_(min) andα′_(max). A ray with a minimal angle, with respect to the vertical axis(α_(min)) should be reflected in the direction of the maximum elevation(α′_(max)) and a ray with a maximum angle (α_(max)) should be reflectedin the direction of the minimum elevation (α′_(min)). Therefore, thewaist of the outgoing beam will be formed in order to minimize thevertical size of the omnidirectional window.

FIGS. 11(a)-11(c) are exemplary illustrations of inverse square lawcompensation using source luminous intensity with angle distributionf′(α′)=1/tan²(α′). FIGS. 11(a)-11(c) illustrate an observer 1220observing light emitted from a light transformer or light source 1210.For analysis, let the spatial light distribution of the light source1210 be described by some known function f(α). Assume that the lighttransformer output luminous intensity distribution, in the verticalplane, is described by and arbitrary function f′(α′), that satisfies thepredetermined custom requirements. For example, if the requirement callsfor equal visibility from different distances (i.e., to compensate forthe inverse square law), this function should be inverse to tan²(α′).The inverse square law results in ${E = \frac{I(\alpha)}{D^{2}}},$where E is illuminance, I is the source luminous intensity and D is thedistance. Because,${D = {{\frac{H}{\tan\quad\alpha}\quad{and}\quad{I(\alpha)}} = {{{EH}^{2}\frac{1}{\tan^{2}\alpha}\quad{or}\quad{f^{\prime}\left( \alpha^{\prime} \right)}} = \frac{c}{\tan^{2}\alpha^{\prime}}}}},$where c is constant.

The design of the reflective surface 1130 is an iterative process. FIG.12 is an exemplary illustration of how a reflective surface 1320 isdesigned step-by-step for the number of emitted rays AB, AC, etc. withincrement Δα. FIG. 12 includes a light source 1310 and an output window1330. If the reflective surface 1320 has been designed from the apexpoint O to point B, the next following point C of the reflective surface1320 can be found from:a·ƒ(a)·Δα=ƒ′(α′)·Δα′  (1)where a is the constant for the full cycle of the design. The conditionin Equation (1) means that output energy in sector Δα′ is equal toemitted energy in the sector Δα with the factor a. Factor a is shown inEquation (2): $\begin{matrix}{{a \cdot {{\int_{o}}^{\alpha_{\max}}{{f(\alpha)} \cdot {\mathbb{d}\alpha}}}} = {\int_{\alpha_{\min}}^{\alpha_{\max}}{{f^{\prime}\left( \alpha^{\prime} \right)} \cdot {\mathbb{d}\alpha^{\prime}}}}} & (2)\end{matrix}$With the output power function ƒ′(α′) the boundary conditions α_(min)and α_(max) will determine factor a unambiguously. So as illustrated inFIG. 12, where α′=α′_(F) andα′_(F)=α′_(L)+Δα′  (3)is the local angle of the reflection cone, β can be found from thereflection's law as: $\begin{matrix}{\beta = \frac{\left( {90^{{^\circ}} - \alpha_{F}^{\prime} + \alpha_{L}^{\prime}} \right)}{2}} & (4)\end{matrix}$The coordinate of point C, which is next to the known point B can befound as the point of intersection of ray AC with the local conicalsurface from the system of linear equations: $\begin{matrix}\left\{ \begin{matrix}{{Y - Y_{B}} = {\tan\quad{\beta \cdot \left( {Z_{C} - Z_{B}} \right)}}} \\{{Y = {{Z \cdot \tan}\quad\alpha}}\quad}\end{matrix} \right. & (5)\end{matrix}$where the second equation is the equation of ray from point A with angleα with respect to the z-axis. So, $\begin{matrix}{Z_{C} = \frac{Y_{B} - {\tan\quad{\beta \cdot Z_{B}}}}{{\tan\quad\alpha} - {\tan\quad\beta}}} & (6)\end{matrix}$and,Y _(C) =Z _(C)·tan α  (7)This can be repeated from point C to the new point of the reflectivesurface 1320 until the outgoing angle α′ will not reach α′_(max).

FIG. 13 is an illustration of an exemplary flowchart for the design of alight transformer by the controller 1050. In step 1405, initial data isreceived by the controller 1050. The initial data can include theminimum angle, the maximum angle, and the location or distance of aninitial design point (AO) of the light transformer with respect to alight source. In step 1410, the controller 1050 calculates anasymmetrical reflective surface constant based on the input minimum andmaximum angles. In step 1415, the controller 1050 sets the initialpoints and angles for the design process. In step 1420, the controller1050 calculates local angles of the reflective surface of the lighttransformer. In step 1425, the controller 1050 calculates thecoordinates of the next point along the reflective surface of the lighttransformer. In step 1430, the controller 1050 calculates the differencein the reflective angle of the reflective surface of the lighttransformer. In step 1435, the controller 1050 sets new points for thereflective surface of the light transformer. In step 1440, thecontroller 1050 determines whether the resulting calculated reflectiveangle is greater than the received minimum angle. If the calculatedreflective angle is not greater than the received minimum angle, thecontroller 1050 returns to step 1420. If the calculated reflective angleis greater than the received minimum angle, the controller 1050 advancesto step 1445. In step 1445, the controller 1050 outputs the final designof the reflective surface of the light transformer. In step 1450, theflowchart ends.

This method illustrates how the controller 1050 can design a lighttransformer to have a predetermined light distribution pattern.Accordingly, the controller 1050 iteratively calculates points on alight transformer to reflect light provided by a light source accordingto received maximum and minimum output angles based on a receivedlocation of a portion of the light transformer.

In some cases, when a single-source luminous intensity distribution doesnot provide adequate illumination to match desired specifications, analternative design with multiple light sources, such as depicted in FIG.5 above, can be implemented. FIGS. 14(a)-14(c) are exemplaryillustrations of a system 1500 that provides an omnidirectional lightpattern in a horizontal plane with a precisely predetermined luminousintensity distribution in the vertical plane. A number of identicallight sources 1510 form a circular array in the horizontal plane (XOY)and are encircled by a toroidal precision optical transformer 1520. Thistransformer 1520 is designed to provide minimal impact of intensitydistribution in the horizontal plane and predetermined precise intensitydistribution in the vertical plane. For example, FIG. 14(b) illustratesa cross-sectional side view of how the transformer provides intensitydistribution from angle β of input light to angle β′ of output lightwhere β/2 and β′/2 represent half of β and β′ respectively.

FIG. 14(c) illustrates how a horizontal pattern is created by way ofoverlapping individual outgoing patterns α′₁, α′₂, α′₃, etc. When givena desired angular intensity distribution for a particular light source1510, it is possible to choose the number of light sources 1510 andtheir relative location to provide a horizontal envelope withpredetermined non-uniformity. FIGS. 15(a) and 15(b) are exemplaryillustrations of the resulting envelope and the overlapping intensitydistribution pattern, respectively, of the system 1500. FIGS. 15(a) and15(b) illustrate an example using 10 LEDs located with equal angularseparation of 36° that provide an envelope with non-uniformity of ±5%.

FIG. 16 is an exemplary illustration of a vertical cross section of atoroidal precision optical transformer 1700. A vertical pattern iscreated by a combination of an aspheric lens 1710 which is the centralpart of the optical transformer (AOB) and members 1720 and 1730. Forexample, member 1730 includes the transformer periphery (CDE). Themembers 1720 and 1730 can include planar optical windows 1740 and 1750and total internal reflection surfaces 1760 and 1770. The aspheric lens1710 transforms all rays emitted in angle $\frac{\beta_{1}}{2}$into the pattern limited by the outgoing ray with angle β′_(max) (ray1′, for example). The periphery performance is based on total internalreflection and, as a result, all rays emitted between angles and$\frac{\beta_{1}}{2}\quad{and}\quad\frac{\beta_{2}}{2}$will be reflected from the total internal reflection surface 1770 andthrough the planar optical window 1750, directed in the domain betweenangles β″_(min) and β″_(max) (for example, ray 2′). Both aspherical lensprofile and total internal reflection surface shapes may be calculatedas functions of predetermined intensity distribution in the verticalplane using methodology and procedures described with respect to FIGS.9-14. This concept and design provides light transformation with a veryhigh ratio$\left( {\frac{\beta}{\beta_{1}}\quad{up}\quad{to}\quad 50} \right)$which is not practical with conventional aspheric optics because ofunreasonable dimensions.

FIG. 17 is an exemplary illustration of an optical transformer for anelevated omnidirectional luminaire. The luminaire can include a lightsource 1810, an input surface 1820, a reflective surface 1830 and alight channel 1840. The light source 1810 can be located a distance dfrom the input surface 1820. Additionally, the input surface can besemispherical about a radius R. Furthermore, the reflective surface 1830can be designed according to the method disclosed with reference toFIGS. 9-14.

In operation, the light source 1810 can transmit light through the inputsurface 1820. The input surface 1820 can direct the light through thelight channel 1840 by way of total internal reflection to the reflectivesurface 1830. The reflective surface 1830 can reflect the lightaccording to a specified distribution pattern. For example, thereflective surface 1830 can reflect the light at an angle α′ where α′falls between α′_(min) and α′_(max). Additionally, the reflectivesurface can reflect the light in a manner similar to the semi-flushomnidirectional luminaire 300 of FIG. 3.

The method of this invention is preferably implemented on a programmedprocessor. However, the method may also be implemented on a generalpurpose or special purpose computer, a programmed microprocessor ormicrocontroller and peripheral integrated circuit elements, an ASIC orother integrated circuit, a hardware electronic or logic circuit such asa discrete element circuit, a programmable logic device such as a PLD,PLA, FPGA or PAL, or the like. In general, any device on which resides afinite state machine capable of implementing the flowcharts shown in theFigures may be used to implement the processor functions of thisinvention.

While this invention has been described with specific embodimentsthereof, it is evident that many alternatives, modifications, andvariations will be apparent to those skilled in the art. Accordingly,the preferred embodiments of the invention as set forth herein areintended to be illustrative, not limiting. Various changes may be madewithout departing from the spirit and scope of the invention.

1. A lighting system, comprising: a housing; a light assembly supportedby the housing, the light assembly including a light source for emittinglight; and a light pipe having a first end in close association with thelight source for coupling the light thereinto, and a second end oppositethe first end from which the light is dispersed; and a light transformerbetween the first end and the second end of the light pipe in closeproximity to the second end with a transformer axis coaxial to thelongitudinal axis of the light pipe, the light transformer having acurved conical reflective surface that redirects and redistributes lightreceived from the light source, wherein the light transformer providesan omnidirectional pattern in a horizontal plane with precalculatedangular luminous intensity distribution in a vertical plane; a powersource operatively connected to the light assembly for providing powerthereto.
 2. The system of claim 1, wherein the light pine is cylindricalin shape.
 3. The system of claim 1, wherein the light pine is tapered,with the first end being the smaller end in which light enters, and thesecond end being the larger end from which the light is dispersed. 4.The system of claim 1, wherein the first end includes a collimatingfeature for collimating the light emitted from the light source.
 5. Thesystem of claim 1, wherein the light source includes a collimatingfeature for collimating the light emitted therefrom.
 6. The system ofclaim 1, further comprising an extension connected to the housing andthe power source for elevating the housing above the surface of theground, which housing, extension, and power source are in asubstantially vertical alignment.
 7. The system of claim 6, wherein theextension includes a frangible portion that fractures according topredetermined criteria.
 8. The system of claim 1, wherein the light isdispersed from the second end in a 360-degree pattern.
 9. The system ofclaim 1, wherein the light is dispersed from the second end in a360-degree pattern around a longitudinal axis that is defined betweenthe first end and the second end.
 10. The system of claim 9, wherein thelongitudinal axis is orientated vertically.
 11. The system of claim 1,wherein the light source is a light emitting diode (LED).
 12. The systemof claim 1, wherein the light source comprises a plurality of LEDs. 13.The system of claim 1, wherein the second end includes a depression thatdefines a conical concavity having a surface from which the light isreflected.
 14. The system of claim 1, wherein the second end includes adepression that defines a conical concavity having a surface containingmultiple apex angles from which the light is reflected.
 15. The systemof claim 1, wherein the second end of the light pipe extends outside ofthe housing such that the light is dispersed in a 360-degree pattern.16. The system of claim 1, further comprising a compound paraboliccoupler interstitial to the light source and the first end for focusingthe light into the first end.
 17. The system of claim 1, furthercomprising an optical coupler interstitial to the light source and thefirst end for focusing light into the first end, which optical couplerincludes a lens combined with a compound parabolic coupler.
 18. Thesystem of claim 1, further comprising an optical coupler interstitial tothe light source and the first end of the light pipe for coupling lightfrom the light source to the first end, wherein the optical coupler isat least one optical fiber having one end in close association with thelight source which is an LED, and the other end interfacing to the firstend of the light pipe.
 19. An elevated airfield luminaire comprising: ahousing; a light assembly, including an LED light source for emittinglight; a cylindrical light pipe having a first end with a semisphericalinput surface located at a focal distance from the light source, thefirst end receiving light from the light source, and a second endlocated opposite the first end, the second end emitting lightomnidirectionally perpendicular to a longitudinal axis of the lightpipe; a light transformer between the first end and the second end ofthe light pipe in close proximity to the second end with a transformeraxis coaxial to the longitudinal axis of the light pipe, the lighttransformer having a curved conical reflective surface that redirectsand redistributes light received from the light source, wherein thelight transformer provides an equal, uniform and omnidirectional patternin a horizontal plane with precalculated angular luminous intensitydistribution in a vertical plane, wherein a cone vertex is located onthe transformer axis.
 20. The elevated airfield luminaire according toclaim 19, wherein the luminaire further comprises: a power sourceoperatively connected to the light assembly.
 21. The luminaire accordingto claim 19, wherein the light pipe is fabricated from optically clearmaterial.
 22. The luminaire according to claim 20, wherein the lighttransformer is integrated into the light pipe as a hollow structureusing total internal reflection, thereby providing the omnidirectionalpattern in the horizontal plane with the precalculated angular luminousintensity distribution in the vertical plane.
 23. A luminaire accordingto claim 19, wherein light diverging from the light pipe in theomnidirectional pattern with a smaller divergency in the vertical planeis concentrated for high efficiency, and the curved reflective surfaceof the light transformer includes a plurality of circular facets,wherein each of the facets reflect light from different angles into thesame limited angular omnidirectional pattern with precalculated angularluminous intensity as a superposition of a set of rays reflected fromdifferent facets.
 24. A lighting system, comprising: a housing; a lightassembly supported by the housing, the light assembly including a lightsource for emitting light; and a light pipe having a first end in closeassociation with the light source for coupling the light thereinto, anda second end opposite the first end from which the light is dispersed;and a light transformer between the first end and the second end of thelight pipe in close proximity to the second end with a transformer axiscoaxial to the longitudinal axis of the light pipe, the lighttransformer having a curved conical reflective surface that redirectsand redistributes light received from the light source, wherein thelight transformer provides an omnidirectional pattern in a horizontalplane with precalculated angular luminous intensity distribution in avertical plane.